Fix the CI for MSRV 1.60

When testing the MSRV, downgrade `tempfile` to v3.6.0 so that it will compile.

.ci_extras/pin-crate-vers-msrv.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+set -eux
+
+# Pin some dependencies to specific versions for the MSRV.
+cargo update -p tempfile --precise 3.6.0

.ci_extras/pin-crate-vers-nightly.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+set -eux
+
+# Pin some dependencies to specific versions for the nightly toolchain.
+cargo update -p openssl --precise 0.10.39
+cargo update -p cc --precise 1.0.61

.cirrus.yml

@@ -50,7 +50,7 @@ linux_arm64_task:
   # pin_deps_script: |
   #   if [ "v$RUST_VERSION" == "v1.60.0" ]; then
   #     echo 'Pinning some dependencies to specific versions'
-  #     cargo update -p <crate> --precise <version>
+  #     ./.ci_extras/pin-crate-vers-msrv.sh
   #   else
   #     echo 'Skipped'
   #   fi

.github/workflows/CI.yml

@@ -61,13 +61,11 @@ jobs:
 
       - name: Pin some dependencies to specific versions (Nightly only)
         if: ${{ matrix.rust == 'nightly' }}
-        run: |
-          cargo update -p openssl --precise 0.10.39
+        run: ./.ci_extras/pin-crate-vers-nightly.sh
 
-      # - name: Pin some dependencies to specific versions (MSRV only)
-      #   if: ${{ matrix.rust == '1.60.0' }}
-      #   run: |
-      #     cargo update -p <crate> --precise <version>
+      - name: Pin some dependencies to specific versions (MSRV only)
+        if: ${{ matrix.rust == '1.60.0' }}
+        run: ./.ci_extras/pin-crate-vers-msrv.sh
 
       - name: Show cargo tree
         uses: actions-rs/cargo@v1

.github/workflows/CIQuantaDisabled.yml

@@ -54,13 +54,11 @@ jobs:
 
       - name: Pin some dependencies to specific versions (Nightly only)
         if: ${{ matrix.rust == 'nightly' }}
-        run: |
-          cargo update -p openssl --precise 0.10.39
+        run: ./.ci_extras/pin-crate-vers-nightly.sh
 
-      # - name: Pin some dependencies to specific versions (MSRV only)
-      #   if: ${{ matrix.rust == '1.60.0' }}
-      #   run: |
-      #     cargo update -p <crate> --precise <version>
+      - name: Pin some dependencies to specific versions (MSRV only)
+        if: ${{ matrix.rust == '1.60.0' }}
+        run: ./.ci_extras/pin-crate-vers-msrv.sh
 
       - name: Run tests (debug, but no quanta feature)
         uses: actions-rs/cargo@v1